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use crate::dsp::{
DspNode, GraphFun, LedPhaseVals, NodeContext, NodeGlobalRef, NodeId, ProcBuf, SAtom,
};
use crate::nodes::{NodeAudioContext, NodeExecContext};
use synfx_dsp::{
process_1pole_highpass, process_1pole_lowpass, process_1pole_tpt_highpass,
process_1pole_tpt_lowpass, process_hal_chamberlin_svf, process_simper_svf,
process_stilson_moog,
};
#[macro_export]
macro_rules! fa_sfilter_type {
($formatter: expr, $v: expr, $denorm_v: expr) => {{
let s = match ($v.round() as usize) {
0 => "LP 1p",
1 => "LP 1pt",
2 => "HP 1p",
3 => "HP 1pt",
4 => "LP 12c",
5 => "HP 12c",
6 => "BP 12c",
7 => "NO 12c",
8 => "LP 12s",
9 => "HP 12s",
10 => "BP 12s",
11 => "NO 12s",
12 => "PK 12s",
13 => "LP 24m",
_ => "?",
};
write!($formatter, "{}", s)
}};
}
#[derive(Debug, Clone)]
pub struct SFilter {
israte: f32,
z: f32,
y: f32,
k: f32,
h: f32,
delay: [f32; 4],
otype: i8,
}
impl SFilter {
pub fn new(_nid: &NodeId, _node_global: &NodeGlobalRef) -> Self {
Self { israte: 1.0 / 44100.0, z: 0.0, y: 0.0, k: 0.0, h: 0.0, delay: [0.0; 4], otype: -1 }
}
pub const inp: &'static str = "Signal input";
pub const freq: &'static str = "Filter cutoff frequency.";
pub const res: &'static str = "Filter resonance.";
pub const ftype: &'static str = "The filter type, there are varying types of \
filters available. Please consult the node documentation for \
a complete list.\n\
Types: **1p/1pt**=one poles, **12c**=Hal Chamberlin SVF,\n\
**12s**=Simper SVF, **24m**=Moog\n\
Outputs: **LP**=Low-,**HP**=High-,**BP**=Band-Pass,**NO**=Notch,**PK**=Peak";
pub const sig: &'static str = "Filtered signal output.";
pub const DESC: &'static str = r#"Simple Filter
This is a collection of more or less simple filters.
There are only two parameters: Filter cutoff ~~freq~~ and the ~~res~~ resonance.
"#;
pub const HELP: &'static str = r#"Simple Audio Filter Collection
This is a collection of a few more or less simple filters
of varying types. There are only few parameters for you to change: ~~freq~~
and ~~res~~ resonance. You can switch between the types with the ~~ftype~~.
There are currently following filters available:
- **HP 1p** - One pole low-pass filter (6db)
- **HP 1pt** - One pole low-pass filter (6db) (TPT form)
- **LP 1p** - One pole high-pass filter (6db)
- **LP 1pt** - One pole high-pass filter (6db) (TPT form)
The Hal Chamberlin filters are an older state variable filter design,
that is limited to max cutoff frequency of 16kHz. For a more stable
filter use the "12s" variants.
- **LP 12c** - Low-pass Hal Chamberlin state variable filter (12dB)
- **HP 12c** - High-pass Hal Chamberlin state variable filter (12dB)
- **BP 12c** - Band-pass Hal Chamberlin state variable filter (12dB)
- **NO 12c** - Notch Hal Chamberlin state variable filter (12dB)
The (Andrew) Simper state variable filter is a newer design
and stable up to 22kHz at 44.1kHz sampling rate. It's overall more precise
and less quirky than the Hal Chamberlin SVF.
- **LP 12s** - Low-pass Simper state variable filter (12dB)
- **HP 12s** - High-pass Simper state variable filter (12dB)
- **BP 12s** - Band-pass Simper state variable filter (12dB)
- **NO 12s** - Notch Simper state variable filter (12dB)
- **PK 12s** - Peak Simper state variable filter (12dB)
For a more colored filter reach for the Stilson/Moog filter with a 24dB
fall off per octave. Beware high cutoff frequencies for this filter,
as it can become quite unstable.
- **LP 24m** - Low-pass Stilson/Moog filter (24dB)
"#;
pub fn graph_fun() -> Option<GraphFun> {
None
}
}
macro_rules! process_filter_fun32 {
($nframes: expr, $inp: expr, $out: ident, $freq: ident, $res: ident,
$input: ident, $minfreq: expr, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame);
let $freq = denorm::SFilter::freq($freq, frame);
let $freq = $freq.clamp($minfreq, $maxfreq);
let $res = denorm::SFilter::res($res, frame);
let $res = $res.clamp(0.0, 0.99);
let s = $block;
$out.write(frame, s);
}
}};
($nframes: expr, $inp: expr, $out: ident, $freq: ident, $res: ident,
$input: ident, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame);
let $freq = denorm::SFilter::freq($freq, frame);
let $freq = $freq.clamp(1.0, $maxfreq);
let $res = denorm::SFilter::res($res, frame);
let $res = $res.clamp(0.0, 0.99);
let s = $block;
$out.write(frame, s);
}
}};
($nframes: expr, $inp: expr, $out: ident, $freq: ident, $res: ident,
$maxres: expr, $input: ident, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame);
let $freq = denorm::SFilter::freq($freq, frame);
let $freq = $freq.clamp(1.0, $maxfreq);
let $res = denorm::SFilter::res($res, frame);
let $res = $res.clamp(0.0, $maxres);
let s = $block;
$out.write(frame, s);
}
}};
($nframes: expr, $inp: expr, $out: ident, $freq: ident,
$input: ident, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame);
let $freq = denorm::SFilter::freq($freq, frame);
let $freq = $freq.clamp(1.0, $maxfreq);
let s = $block;
$out.write(frame, s);
}
}};
}
macro_rules! process_filter_fun {
($nframes: expr, $inp: expr, $out: ident, $freq: ident, $res: ident,
$input: ident, $minfreq: expr, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame) as f64;
let $freq = denorm::SFilter::freq($freq, frame) as f64;
let $freq = $freq.clamp($minfreq, $maxfreq);
let $res = denorm::SFilter::res($res, frame) as f64;
let $res = $res.clamp(0.0, 0.99);
let s = $block;
$out.write(frame, s as f32);
}
}};
($nframes: expr, $inp: expr, $out: ident, $freq: ident, $res: ident,
$input: ident, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame) as f64;
let $freq = denorm::SFilter::freq($freq, frame) as f64;
let $freq = $freq.clamp(1.0, $maxfreq);
let $res = denorm::SFilter::res($res, frame) as f64;
let $res = $res.clamp(0.0, 0.99);
let s = $block;
$out.write(frame, s as f32);
}
}};
($nframes: expr, $inp: expr, $out: ident, $freq: ident, $res: ident,
$maxres: expr, $input: ident, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame) as f64;
let $freq = denorm::SFilter::freq($freq, frame) as f64;
let $freq = $freq.clamp(1.0, $maxfreq);
let $res = denorm::SFilter::res($res, frame) as f64;
let $res = $res.clamp(0.0, $maxres);
let s = $block;
$out.write(frame, s as f32);
}
}};
($nframes: expr, $inp: expr, $out: ident, $freq: ident,
$input: ident, $maxfreq: expr, $block: block) => {{
for frame in 0..$nframes {
let $input = $inp.read(frame) as f64;
let $freq = denorm::SFilter::freq($freq, frame) as f64;
let $freq = $freq.clamp(1.0, $maxfreq);
let s = $block;
$out.write(frame, s as f32);
}
}};
}
impl DspNode for SFilter {
fn set_sample_rate(&mut self, srate: f32) {
self.israte = 1.0 / srate;
}
fn reset(&mut self) {
self.z = 0.0;
self.y = 0.0;
self.k = 0.0;
self.h = 0.0;
self.delay = [0.0; 4];
self.otype = -1;
}
#[inline]
fn process(
&mut self,
ctx: &mut dyn NodeAudioContext,
_ectx: &mut NodeExecContext,
_nctx: &NodeContext,
atoms: &[SAtom],
inputs: &[ProcBuf],
outputs: &mut [ProcBuf],
ctx_vals: LedPhaseVals,
) {
use crate::dsp::{at, denorm, inp, out};
let inp = inp::SFilter::inp(inputs);
let freq = inp::SFilter::freq(inputs);
let res = inp::SFilter::res(inputs);
let ftype = at::SFilter::ftype(atoms);
let out = out::SFilter::sig(outputs);
let ftype = ftype.i() as i8;
if ftype != self.otype {
self.y = 0.0;
self.z = 0.0;
self.k = 0.0;
self.h = 0.0;
self.delay = [0.0; 4];
self.otype = ftype;
}
match ftype {
0 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, input, 22000.0, {
process_1pole_lowpass(input, freq, self.israte, &mut self.z)
})
}
1 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, input, 22000.0, {
process_1pole_tpt_lowpass(input, freq, self.israte, &mut self.z)
})
}
2 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, input, 22000.0, {
process_1pole_highpass(input, freq, self.israte, &mut self.z, &mut self.y)
})
}
3 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, input, 22000.0, {
process_1pole_tpt_highpass(input, freq, self.israte, &mut self.z)
})
}
4 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, input, 2.0, 16000.0, {
let (_high, _notch) = process_hal_chamberlin_svf(
input,
freq,
res,
self.israte,
&mut self.z,
&mut self.y,
);
self.y
});
}
5 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, input, 16000.0, {
let (high, _notch) = process_hal_chamberlin_svf(
input,
freq,
res,
self.israte,
&mut self.z,
&mut self.y,
);
high
});
}
6 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, input, 16000.0, {
let (_high, _notch) = process_hal_chamberlin_svf(
input,
freq,
res,
self.israte,
&mut self.z,
&mut self.y,
);
self.z
});
}
7 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, input, 16000.0, {
let (_high, notch) = process_hal_chamberlin_svf(
input,
freq,
res,
self.israte,
&mut self.z,
&mut self.y,
);
notch
});
}
8 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, 1.0, input, 22000.0, {
let (low, _band, _high) =
process_simper_svf(input, freq, res, self.israte, &mut self.k, &mut self.h);
low
});
}
9 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, 1.0, input, 22000.0, {
let (_low, _band, high) =
process_simper_svf(input, freq, res, self.israte, &mut self.k, &mut self.h);
high
});
}
10 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, 1.0, input, 22000.0, {
let (_low, band, _high) =
process_simper_svf(input, freq, res, self.israte, &mut self.k, &mut self.h);
band
});
}
11 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, 1.0, input, 22000.0, {
let (low, _band, high) =
process_simper_svf(input, freq, res, self.israte, &mut self.k, &mut self.h);
low + high
});
}
12 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, 1.0, input, 22000.0, {
let (low, _band, high) =
process_simper_svf(input, freq, res, self.israte, &mut self.k, &mut self.h);
low - high
});
}
13 => {
process_filter_fun32!(ctx.nframes(), inp, out, freq, res, 1.0, input, 20000.0, {
let input = input.clamp(-1.0, 1.0);
process_stilson_moog(
input,
freq,
res,
self.israte,
&mut self.z,
&mut self.y,
&mut self.k,
&mut self.h,
&mut self.delay,
)
});
}
_ => {}
}
ctx_vals[0].set(out.read(ctx.nframes() - 1));
}
}
